Electric motor whine

<div class='quotetop'>QUOTE(bmwquickspeed @ May 30 2007, 12:14 PM) [snapback]452225[/snapback]</div>

If you've ever driven the Prius on a very long decent you know the answer to this 'cause it's an easy one...

Once the battery fills up the car stops regenerative braking completely and you're now on good old fashioned brake pads. If you use engine braking you don't burn away at the brake pads as much because a lot of energy is being used to pump and compress air in the ICE. The first time I experienced this exact scenario was on my way over the coastal range into Pismo Beach and if you'll excuse the anthropomorphism, the Prius acts downright frantic when the battery goes all green.

If the battery is full AND you put it into 'B' it will still engine brake and it makes a ton of noise doing it

 

The only annoying whine in a Prius is from your spouse or partner, all others are normal

 

Thanks I have only had my car for a couple of months and have yet to go on a decline long enough to get all green.

I guess my drive back from flagstaff next month will be my first opportunity.

Now I understand why I would want to use the engine braking. Thanks Platypus.